AD7877 Analog Devices, AD7877 Datasheet - Page 43

• Manufacturer Part Number: AD7877
• Description: Touch Screen Controller
• Manufacturer: Analog Devices

Specifications of AD7877

• Resolution (bits): 12bit
• # Chan: 9
• Sample Rate: 125kSPS
• Interface: Ser
• Analog Input Type: SE-Uni
• Ain Range: Uni (Vref),Uni 2.5V
• Adc Architecture: SAR
• Pkg Type: CSP

Data Sheet
Register Name: GPIO Control Register 2
Write Address:
Read Address:
Default Value:
Type:
Table 23.
Bit
0
1
2
3
4
5
6
7
Register Name: GPIO Data Register
Write Address:
Read Address:
Default Value:
Type:
Table 24.
Bit
0
1
2
3
4
5
6
7
Name
GPIO4_ALEN
GPIO4_DIR
GPIO4_POL
Not Used
GPIO3_ALEN
GPIO3_DIR
GPIO3_POL
GPIO3_EN
Name
Not used
Not used
Not used
Not used
GPIO4_DAT
GPIO3_DAT
GPIO2_DAT
GPIO1_DAT
[1111] 0001
11100
0x000
Read/write
[1111] 0010
11101
0x000
Read/write
Read/Write
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Read/Write
R/W
R/W
R/W
R/W
Description
If this bit is 1, GPIO4 is an interrupt source for the ALERT output; clearing this bit masks out GPIO3
as an interrupt source for the ALERT output
This bit sets the direction of GPIO4
0 = output
1 = input
This bit determines if GPIO4 is active high or low
0 = active low
1 = active high
This bit is not used
If this bit is 1, GPIO3 is an interrupt source for the ALERT output; clearing this bit masks out GPIO4
as an interrupt source for the ALERT output
This bit sets the direction of GPIO3
0 = output
1 = input
This bit determines if GPIO3 is active high or low
0 = active low
1 = active high
This bit selects the function of AUX3/GPIO3
0 = AUX3
1 = GPIO3
Description
This bit is not used
This bit is not used
This bit is not used
This bit is not used
GPIO4 data bit
GPIO3 data bit
GPIO2 data bit
GPIO1 data bit
Rev. D | Page 43 of 44
AD7877